9 week old ebf dropping centiles fast

DS was born between the 98th and 91st centile. He is now 9 weeks, and after cruising along on the 75th centile for a while, has now dropped to between the 75th and 50th centiles. I know I shouldn't take much notice but HV wants me to see the GP.

DS has reflux, and was on Gaviscon (now on ranitidine). He poos practically after each feed, explosive watery poos, sometimes yellow and sometimes with a green tinge. We've all been unwell lately, and I'm wondering if this is affecting him. He's always had explosive runny poos since birth though.

My diet is reasonable-have cut out dairy due to DS having CMPI. I'm drinking lots and DS has lots of wet, and dirty nappies.

What would you all advise? DS is generally a happy chap-goes 2 hours between feeds daytime and 4-5 hours at night. He bfs for 10-40 minutes depending on how hungry he is. I ALWAYS offer the second breast but he is rarely interested.

Should I be worried about dropping centiles? He is currently 5.8 kgs (having put on 250g in 2 weeks).

I'd go see a breastfeeding advisor before going to the doctor. Do you have a local La Leche League group near you? They can make sure that everything is absolutely hunky dory when it comes to feeding and advise on ways to help with weight gain. It could be that the latch could do with slight tweaking or something else fairly simple. A doctor wouldn't know this... and would automatically advise top ups in a lot of situations

Something is making me wonder about a tongue tie, the poo's and the reflux, there is a great support thread on here that will be able to give you much more advice than I can, have you had him? (can't check if you said dd or DS cos in in my phone!!) well done for sticking with bf and good luck

Their latch can change as they grow - a previous good hold could turn into a bad one as their bodies grow, and without you noticing. It's always worth getting latch checked... even if that isn't the problem, it is worth ruling it out as its easy to fix. Plus if baby is very gassy it could be because they are taking in air while feeding - again something which 'could' be down to latch. It might just be a bit of tweaking that is needed.

Having experience of this (and still experiencing the poo issue!), I'd get him fully checked for tongue/lip tie.

Also, my dd has suspected cmpi - we have our 8 week check tomo and I and asking to be referred to a paediatric allergy specialist, as although things are better, she is still reacting to something, and I've also cut soy and eggs, and I'm careful at checking all ingredients.

Could your DS be allergic to something else? A significant proportion of children with cmpi are also allergic to soy. There is a lot of hidden dairy and soy in food.